Checking in on the recently filled lambic barrels

Last weekend I went up to check on the barrels from our brew day a couple months ago.  Given that this was the first time using a coolship, I was a little anxious to see how they were doing.

Taking a step back, I realize I haven't written anything about the brew day itself.  It was a full weekend and somehow everything went off without a hitch.  There is a great write up here summarizing the weekend better than I could.  The brewers at O'so have got the process down and are very efficient at doing what they do. Compared to previous years (which I have notes posted), there is very to add regarding the brewing.  Post-brew however, the wort went from the boil kettle to the coolship that had been temporarily installed outside under a large tent to rest overnight.

Coolship filling with lambic wort.  (photo credit)

From literature on the process, I was hoping the wort would be ~70°F the next morning.  We got in around 8:30 am and checked it with a digital thermometer which read 70°F exactly.  I was ecstatic to say the least. The inoculated wort was then pumped into a large tank to ensure everything was homogeneous, and then pumped into barrels.  Some of the barrels filled were straight from the winery and some of the barrels filled were previously emptied lambic barrels.  They were all thoroughly cleaned out with 200°F water prior to filling.

So, back to being up there and checking in on the barrels.  I was able to taste from barrels that had previously held our lambic, but the barrels that were our first use were tucked away such that we couldn't get to them without a forklift.  There was an event going on at the brewery, so I'll wait for another day to check in on those.  I am curious to see if there will be a distinction between the two sets of barrels.

I am a firm believer that, while a coolship imparts a new generation of microflora into the wort, much of the fermentation process is guided by the yeast/bacteria already in the barrel.  Cleaning the barrel, even at the high temperatures we do, will never sanitize the barrels completely and yeast/bacteria residing deeper in the wood will survive.  Through generations of culling barrels, a brewery is able to build a "house flavor".  You will find others who argue the relative impact of the coolship on the fermentation process is greater than that of the barrel.  Its an interesting argument if you really like nerding out about this stuff, and having these two sets of barrels is my way of testing things out.

It was interesting to taste the barrels that were accessible.  At this age there is little you can tell about how the beer will turn out, but I am able to see if its "on track".  First, I am making sure it did in fact ferment instead of spoil.  Given this was the first time spontaneously fermenting via coolship, that concern was lingering in the back of my mind.  But everything checked out.  It actually tasted almost exactly as the previous year's barrels did at this point.  It has a light tartness and an ever so slight brett character. The only difference I noticed from prior batches was there was a sweet lime flavor.  Is this an impact of local microflora?  In addition to these flavors, there is this phenolic flavor which we've noticed in previous batches as well. Its just an odd stage our lambic goes through. The reason I mention this is so home brewers who may be reading this know that these early off flavors are not a reason to dump your beer.  Honestly, there is no reason to even taste your lambic in the first 9 months.  I just do it for fun and because I can pull out of a sample port below the pellicle line.

O'so Brewday & 1 year mark.

Two major events occurred this weekend.  On Friday, we brewed the second batch of lambic up at O'so Brewing, and today marks 1 year from the day I filled that first pilot barrel.  Its crazy how much a year can make a difference.  I went from being thrilled to get a single barrel filled to frustrated we didn't fill 15 barrels on Friday.

I'm not going to outline the process or talk too much on the brewing itself as I would just be repeating the previous brewday.  Instead, I'll mention a few of the changes between the batches.  The last batch hit 1.040 gravity, which is fine, but its on the lower end of the spectrum.  This time we upped the grain bill and hit 1.054.  In doing this we also got a darker wort, and I really like the color that resulted.

Another factor that helped us hit a higher gravity was the evaporation rate during the 4 hour boil, which is higher in the winter than the summer.  While I am happy to have the higher gravity, we only filled 13 barrels.  A 14th barrel was filled half way, and we will use that to top off the other 13 barrels after the active fermentation stage finishes.  In comparison, last year we easily filled 14 barrels and had probably 1.5 barrels worth of wort that had no barrel to go into and therefore went down the drain.

Filling the inoculated barrels

We also changed the hopping.  Last year we used 38 pounds of 5 year old Liberty hops.  In sampling the lambic at 6 months old, it has a fairly pronounced hop character.  I know this will fade, and have seen that happen to my pilot barrel, but we wanted to dial that down a notch and used 30 pounds of 5 year old Willamette hops.  The hop variety was not an intentional change, but rather simply what was available.

Measuring out 30# and breaking up the whole hops.

The most significant change we made this batch was to not pitch yeast.  Instead, we took the lambic barrels from batch 1 and transferred the contents over to new barrels.  Then we filled the inoculated barrels with fresh wort and will let it ferment with resident yeast in the barrel.  The "new" barrels were used wine barrels, and we soaked them for a month in water to further extract any tannin and wine flavor, then steam cleaned them.  I realize this lambic is going into new barrels twice and so wanted to make sure to increase my effort to strip flavor from the new barrels.  To rack the lambic from one barrel to another, we used a Bulldog barrel transfer set up.  First we pre-charged the empty barrels with CO2, then used CO2 to pressurize the filled barrel and gently push the lambic over to its new home.

Transferring aged lambic into "new" barrels.

All in all, it was another successful brew day.  Although I was especially disappointed in not being able to fill that 14th and 15th barrel, it is good to reflect on the year and realize how far this project has come.  I am thankful to O'so for brewing this beer with me, and I look forward to our annual brew day.

A sea of barrels.  All but the 6 stacked are for lambic.

Update:
It took 4 days to kick in, but fermentation is foaming over.

It started with these two on Tuesday night, and by Wednesday morning all of the barrels were foaming.  While I like that there was a stressed fermentation that took a few days to start, the barrels were in the way of brewing operations and needed to be moved into the tap house.  However, Wednesday morning it was learned that the concrete floors in that area do not slope to the floor drain and all of the foam pooled up and poured into the adjoining room; Marc's office.  While I imagine it smells wonderful, it will require quite a bit of clean up, and the barrels were moved back over the floor drain.  Reminds me of the mess I had with the pilot barrel!

O'so Collaboration: Day 50

I went back up to O'so yesterday to check on the barrels and install the sample port.  It has already been 50 days since we brewed the lambic!  Wow, time flies.  However, when you consider the beer will have to age close to 2 years, that isn't much time at all.  At this point in the game, it is more of a sensory check for off flavors.  I am expecting it to taste/smell essentially like a berliner weisse.  I was also curious if there would be any differences between the barrels.  There are 14 barrels, so hopefully they will develop differently and we will have some diversity to blend with.

Drill a 7/64" hole and catch a sample

As expected, they all taste/smell like a berliner weisse, which is a good sign.  We are on the right track.  There wasn't a whole lot of variety (obviously it is still very young), but there was some.  Some barrels were more lemongrass, some were more minerally, some were more brett/funky.  Aside from tasting and smelling the beer, it is a good chance to take a gravity reading.  All the barrels we tested were hovering around 5 brix (1.009 SG).

Testing gravity with a refractometer. 

All and all I am pretty happy with the progress.

O'so Collaboration: Brewday

Jump to:
Installing a Drain Port
Filling the Barrels

We were at the O'so brewery at 6:00am, and didn't finish until 11:00pm.  It was a long brew-day to say the least. Marc and his head brewer, Mike, had planned and prepped the turbid mash schedule as best as one could, now it was time to actually go through the steps and learn/adjust along the way.  It was incredible watching these two brew an unfamiliar style, yet hit every target number along the way.  We had some troubles with the grain mill at the start of the day, and the initial dough in was very challenging, but after that, the process went nearly perfect.

Richard adding rice hulls to the Mash Tun.

I tried to take pictures throughout the day, but many of them didn't turn out because of the steam coming out of the kettle.  There was a student there filming and photographing the process, so I may get some of his pictures soon.

Protein cake.

I believe the above picture was taken during the final transfer of the turbid mash.  As you can see, a large layer of protein has developed on top of the grain bed (even separating away from the wall).  The next picture is the wort transferring over to the boil kettle.  They were very happy with how clean it was!

Transferring to boil kettle.

As the kettle was being filling, they started the boil.  It took nearly an hour to fill the kettle with 35 barrels of wort, and it was boiling the entire time.  During that time we added the hops.  We used 40 pounds of 5 year old Liberty hops.  They smelled like a hockey locker room.

5 year old hops

Some people assume that Lambics don't have much hops in them, but there are IPA's that use less hops than Lambics.  The only difference is that they have been aged, which removes the bitter flavor of the hops, but retains its antimicrobial power.  The boil went for 4 hours.  Then the wort was transferred over to the whirlpool and left the hops behind.  Wow do those hops ever expand!

Hops at the bottom of the Boil Kettle

At this point that hops mass is about 8" deep and absorbing nearly 3 barrels of the wort.  Marc cleaned this tank the following day and told me they had puffed up and it was about 2 feet deep!

Installing the Drain Port:

While much of the brewing process was going on, I was further prepping the barrels.  We had to install the drain port prior to filling these barrels.  I talked to Vinnie at Russian River and he sent me over the instructions on how to do it.  Its always nerve racking drilling a whole into the barrel, so it was nice to know the exact method.

Drilling a 15/16" hole into the barrel head.

The hole is about 2 fingers up from the edge.

Insert a standard Belgian cork into the hole.

It is quite simple.  The French Oak is pretty hard and can be a bit of a pain to drill through.  We tried a couple different ways of inserting the cork on our practice 2x4.  It is possible to hammer the cork in, but if you use a simple floor model corker, you can pull the handle part way so it just compresses the cork.  The cork has a bit of memory at that compressed state giving you enough time to easily slide the cork into the hole.  It will then quickly expand back to its normal state creating a very tight seal in the barrel.

Filling the Barrels:

So with the barrels prepped and the wort ready, it was time to fill the barrels.  Initially our plan was to short fill the barrels and then after the primary had finished, to rack over the contents of two of the barrels to top off the other 12.  As it happened, we had yielded more wort that estimated, and so we filled all 14 barrels to the top (stopping half way to add the yeast).

Filling the barrel with lambic wort.

Since this is the first use for these barrels, we needed to add a blend of yeast/bacteria to the barrel, which we did half way through filling each (1 liter of wort per barrel).  Future uses of these barrels will not require yeast to be pitched.  We used the same East Coast Yeast blend that I used for my pilot barrel.  I can't stress enough how happy I have been with this yeast.  Thank you Al!

Adding East Coast Yeast lambic blend to the barrel.

And so, 17 hours after we started, we have 14 barrels of lambic sitting over the drain waiting for fermentation to start.

I figured it would be 2 days before the fermentation kicked off, but Marc sent me this picture the next day:

Fermentation in less than 12 hours!

O'so Collaboration

Over the weekend I went up to start the preparation work for what will become a collaborative O'so/Funk Factory lambic project.

(click picture to visit the O'so website)

I arrived Friday evening to 14, French Oak, used wine barrels delivered and waiting for me.

While I had the barrels on end, I decided to quick apply a stencil I made up for them.  Its a simplified version of the FF logo, and creates 4 spaces to record the fill date.  With that done, it was time to line up the barrels and fill them with water.

Soaking the barrel overnight was done for two reasons.  First, it will swell the barrel ensuring there are no leaks when it comes time to fill it with lambic wort.  Secondly, it will extract some of the wine flavor from the barrel.  In brewing lambic, you want as neutral of a barrel as possible.  When I arrived to the very last barrel and filled it up, I noticed it wasn't holding water.  On the barrel head opposite to me, it was gushing out water along the bottom croze.  I left the hose valve 1/3 of the way open, and it was losing water faster than the hose filled it.  Unfortunately, I think that barrel will need to be replaced even though it did swell up overnight.  I just don't have any confidence in a barrel that struggles that much to hold water that it will limit O2 permeation sufficiently.

The next morning I had to empty the barrels.  Moving around a 60 gallon filled barrel is no easy task, and in fact took me most the morning to empty all 14 barrels.  It wasn't until nearly noon that I started steaming the barrels.

This is the same steamer I used before.  Behind the barrel in the picture being steamed are 4 that I had already completed.  You can see the bung is in and seals the barrel.  As the steam cools down, it creates a vacuum that will extract more wine from the wood.  Once I finished with all the barrels, I gave them a final hot water rinse and sealed them again.  The air inside was hot from the water, so they will be vacuum sealed until the day we go to fill them with wort.